cm is what

= comment

n.[C][U]
1. 註釋,評註[(+on/about)]
2. 批評,意見,評論[(+on/about)]
He made no comments on our proposal.
他對我們的建議沒有作評論。
3. 閒話,議論[(+on/about)]
His conduct at social gatherings created a lot of comment.
他在社交聚會上的表現引起許多閒話。

CM=ComMent評論
圖片參考：http://tw.yimg.com/i/tw/ugc/rte/smiley_35.gif